Finite element modeling with patient-specific geometry to assess clinical risks of percutaneous pulmonary valve implantation.

BACKGROUND: Percutaneous pulmonary valve implantation (PPVI) is a non-surgical treatment for right ventricular outflow tract (RVOT) dysfunction. During PPVI, a stented valve, delivered via catheter, replaces the dysfunctional pulmonary valve. Stent oversizing allows valve anchoring within the RVOT, but overexpansion can intrude on the surrounding structures. Potentially dangerous outcomes include aortic valve insufficiency (AVI) from aortic root (AR) distortion and myocardial ischemia from coronary artery (CA) compression. Currently, risks are evaluated via balloon angioplasty/sizing before stent deployment. Patient-specific finite element (FE) analysis frameworks can improve pre-procedural risk assessment, but current methods require hundreds of hours of high-performance computation. METHODS: We created a simplified method to simulate the procedure using patient-specific FE models for accurate, efficient pre-procedural PPVI (using balloon expandable valves) risk assessment. The methodology was tested by retrospectively evaluating the clinical outcome of 12 PPVI candidates. RESULTS: Of 12 patients (median age 14.5 years) with dysfunctional RVOT, 7 had native RVOT and 5 had RV-PA conduits. Seven patients had undergone successful RVOT stent/valve placement, three had significant AVI on balloon testing, one had left CA compression, and one had both AVI and left CA compression. A model-calculated change of more than 20% in lumen diameter of the AR or coronary arteries correctly predicted aortic valve sufficiency and/or CA compression in all the patients. CONCLUSION: Agreement between FE results and clinical outcomes is excellent. Additionally, these models run in 2-6 min on a desktop computer, demonstrating potential use of FE analysis for pre-procedural risk assessment of PPVI in a clinically relevant timeframe.

Early Outcomes From a Multicenter Transcatheter Self-Expanding Pulmonary Valve Replacement Registry.

BACKGROUND: Transcatheter pulmonary valve replacement (TPVR) with the self-expanding Harmony valve (Medtronic) is an emerging treatment for patients with native or surgically repaired right ventricular outflow tract (RVOT) pulmonary regurgitation (PR). Limited data are available since U.S. Food and Drug Administration approval in 2021. OBJECTIVES: In this study, the authors sought to evaluate the safety and short-term effectiveness of self-expanding TPVR in a real-world experience. METHODS: This was a multicenter registry study of consecutive patients with native RVOT PR who underwent TPVR through April 30, 2022, at 11 U.S. CENTERS: The primary outcome was a composite of hemodynamic dysfunction (PR greater than mild and RVOT mean gradient >30 mm Hg) and RVOT reintervention. RESULTS: A total of 243 patients underwent TPVR at a median age of 31 years (Q1-Q3: 19-45 years). Cardiac diagnoses were tetralogy of Fallot (71%), valvular pulmonary stenosis (21%), and other (8%). Acute technical success was achieved in all but 1 case. Procedural serious adverse events occurred in 4% of cases, with no device embolization or death. Hospital length of stay was 1 day in 86% of patients. Ventricular arrhythmia prompting treatment occurred in 19% of cases. At a median follow-up of 13 months (Q1-Q3: 8-19 months), 98% of patients had acceptable hemodynamic function. Estimated freedom from the composite clinical outcome was 99% at 1 year and 96% at 2 years. Freedom from TPVR-related endocarditis was 98% at 1 year. Five patients died from COVID-19 (n = 1), unknown causes (n = 2), and bloodstream infection (n = 2). CONCLUSIONS: In this large multicenter real-world experience, short-term clinical and hemodynamic outcomes of self-expanding TPVR therapy were excellent. Ongoing follow-up of this cohort will provide important insights into long-term outcomes.

Bilateral Harmony™ valve placement in branch pulmonary arteries.

While newer self-expanding pulmonic valves were primarily designed for larger right ventricular outflow tracks, there are instances where even larger anatomies cannot accommodate these devices. In this report, we describe the successful implantation of two Harmony™ valves in bilateral branch pulmonary arteries after exhausting other options.

The adaptability of the Pulsta valve to the diverse main pulmonary artery shape of native right ventricular outflow tract disease.

BACKGROUND: Pulsta valve is increasingly used for percutaneous pulmonary valve implantation (PPVI) in patients with a large native right ventricular outflow tract (RVOT). This study aims to elucidate the outcomes of Pulsta valve implantation within the native RVOT and assess its adaptability to various native main pulmonary artery (PA) anatomies. METHODS: A multicenter retrospective study included 182 patients with moderate to severe pulmonary regurgitation in the native RVOT who underwent PPVI with Pulsta valves® between February 2016 and August 2023 at five Korean and Taiwanese tertiary referral centers. RESULTS: Pulsta valve implantation was successful in 179 out of 182 patients (98.4%) with an average age of 26.7 ± 11.0 years. The median follow-up duration was 29 months. Baseline assessments revealed enlarged right ventricle (RV) volume (mean indexed RV end-diastolic volume: 163.1 (interquartile range, IQR: 152.0-180.3 mL/m²), which significantly decreased to 123.6(IQR: 106.6-137.5 mL/m2  after 1 year. The main PA types were classified as pyramidal (3.8%), straight (38.5%), reverse pyramidal (13.2%), convex (26.4%), and concave (18.1%) shapes. Pulsta valve placement was adapted, with distal main PA for pyramidal shapes and proximal or mid-PA for reverse pyramidal shapes. Two patients experienced Pulsta valve embolization to RV, requiring surgical removal, and one patient encountered valve migration to the distal main PA, necessitating surgical fixation. CONCLUSIONS: Customized valve insertion sites are pivotal in self-expandable PPVI considering diverse native RVOT shape. The rather soft and compact structure of the Pulsta valve has characteristics to are adaptable to diverse native RVOT geometries.

Morphometrics predicts the differential regurgitant fraction in bilateral pulmonary arteries of patients with repaired tetralogy of fallot.

In patients with repaired tetralogy of Fallot (rTOF), the regurgitant fraction (RF) in left pulmonary artery (LPA) and right pulmonary artery (RPA) is usually unequal. The morphometrics may play a crucial role in this RF discrepancy. Cardiovascular MR of 79 rTOF patients and 20 healthy controls were retrospectively enrolled. Forty-four from the 79 patients were matched in age, sex and body surface area to the 20 controls and were investigated for: (1) phase-contrast flow of main pulmonary artery (MPA), LPA, and RPA; (2) vascular angles: the angles between the thoracic anterior-posterior line (TAPL) with MPA (θM-AP), MPA with RPA (θM-R), and MPA with LPA (θM-L); (3) cardiac angle, the angle between TAPL and the interventricular septum; (4) area ratio of bilateral lung and hemithorax regions. Compared with the 20 controls, the 44 rTOF patients exhibited wider θM-AP, sharper θM-L angle, and a smaller θM-L/θM-R ratio. In the 79 rTOF patients, LPA showed lower forward, backward, and net flow, and greater RF as compared with RPA. Multivariate analysis showed that the RF of LPA was negatively associated with the θM-L/θM-R ratio and the age at surgery (R2 = 0.255). Conversely, the RF of RPA was negatively associated with the left lung/left hemithorax area ratio and cross-sectional area (CSA) of LPA, and positively associated with CSA of RPA and MPA (R2 = 0.366). In rTOF patients, the RF of LPA is more severe than that of RPA, which may be related to the vascular morphometrics. Different morphometric parameters are independently associated with the RF of LPA or RPA, which may offer potential insights for surgical strategies.

Flow pattern analysis of right ventricular outflow tract in repaired tetralogy of Fallot through 4D flow MRI.

Cardiac magnetic resonance imaging (CMR) often shows discrepancies between right ventricular outflow tract (RVOT) flow and left ventricular outflow tract flow in patients with late-stage repaired tetralogy of Fallot (rTOF), leading to potential errors in pulmonary regurgitation fraction (PRF) assessment. This study aimed to identify the conditions under which RVOT flow can be acutely evaluated using four-dimensional (4D) flow CMR. Twenty-seven consecutive patients with rTOF underwent both two-dimensional phase-contrast (2D PC) and 4D flow CMR between 2016 and 2018, excluding those with peripheral pulmonary artery stenosis, RVOT conduit replacement, unknown surgical method, and an aortic valve regurgitation greater than 20%. Seven healthy controls also underwent only 4D Flow CMR. All healthy controls and fifteen patients with rTOF showed laminar RVOT flow, while seven patients exhibited helical, and four patients exhibited vortical RVOT flow in 4D flow CMR visualization. Flow-volume concordance between the pulmonary artery and aortic flow was significantly lower in patients with rTOF and PRF > 40% in 2D PC CMR. This concordance rate in the suprapulmonary valve was high in both the TOF and control groups, comparing at five RVOT locations in 4D flow CMR. Regarding RVOT flow regurgitation in 4D flow, the whole bulk evaluation exhibited greater variation depending on the flow type compared to the whole pixel-wise evaluation. The study confirmed the flow volume at the upper section of the pulmonary valve as the most accurate correlate of aortic flow volume. Furthermore, the 4D flow CMR using the pixel-wise method demonstrated superior accuracy compared to the traditional bulk flow method.

Transcatheter pulmonary valve replacement in surgically-created double-barrel right ventricular outflow tracts: A single center case-series.

This manuscript describes the feasibility and approach to the assessment and performance of transcatheter pulmonary valve replacement (tPVR) in patients with surgically-created "double-barrel" right ventricular outflow tracts (RVOT). Patients with tetralogy of Fallot may have coronary anomalies which prohibit the performance of traditional tetralogy of Fallot repair. In certain cases, this may necessitate the placement of a right ventricle to pulmonary artery conduit in addition to the native RVOT, which is left in situ, creating so-called "double-barrel" RVOTs. When these patients develop RVOT dysfunction later in life, they would typically be referred for reoperation due to concerns for risk of coronary compression associated with a transcatheter approach. However, whether a transcatheter approach with valve replacement in the native RVOT is feasible or safe is unknown. This was a retrospective review of patients with a surgically created "double-barrel" RVOTs who underwent cardiac catheterization for assessment of tPVR at Boston Children's Hospital. From July 2012 to July 2022, there were four patients with "double-barrel" RVOTs who underwent assessment for tPVR. The age at catheterization ranged between 22 and 39 years. In three out of four patients, coronary compression testing was negative. These three patients had successful tPVR in the native RVOT. At follow up, all three patients were free of greater than mild regurgitation by echocardiogram and had a maximum instantaneous gradient across the RVOT ranging between 20 and 33 mmHg. Performance of tPVR in patients with surgically created "double-barrel" RVOTs is feasible. The safety of this procedure depends crucially on coronary artery assessment at all stages.

Multicenter Experience for Early and Mid-Term Outcome of MyVal Transcatheter Pulmonary Valve Implantation.

Transcatheter pulmonary valve implantation (TPVI) is a surgical alternative for correcting dysfunctional right ventricular outflow tract in previously operated patients. MyVal transcatheter heart valve (THV) (Meril Life Sciences, India), a new transcatheter valve designed for aortic position has recently been reported to be implanted in pulmonary position. Myval transcatheter valve were implanted in patients with stenosed dysfunctional conduits, severe regurgitation from transannular patch or dysfunctional surgical pulmonary valves (Bioprosthesis). Procedural details and post-TPVI follow-up were analysed. Myval TPVI was used in Fifty three patients with median age of 15 years (IQR 12-19.5 years). Almost sixty percent of the patients were male, with a median weight of 50 kg (31-63 kg). Prestenting was used in more than 80 percent of patients (n = 45 patients), while 6 patients had a prior surgical valve implantation. After Myval TPVI implantation, the peak instantaneous gradient across the RVOT decreased from a median of 23.5 mmHg (IQR 10-53 mmHg) pre-procedure to 10 mmHg (IQR 5-16 mmHg) post-procedure. The median fluoroscopy time for the procedure was 35 min (IQR 23.5-44 min). The large sizes-mainly the 29-mm and 32 mm Myval (Navigator, Meril Life Sciences Pvt Ltd, India), were the most used size in 40% (n = 22) of the cases each. The median contrast volume used during the procedure was 247 mL (IQR 120-300 mL). Patients were followed for a median period of 360 days (IQR 164-525 days). At the last clinic follow-up, there was no tricuspid valve regurgitation. Moderate neo-pulmonary valve regurgitation was reported in three cases. Early experience of TPVI with MyVal is encouraging with procedural success in all patients and acceptable mid-term outcomes.

Predictive value of Cardiac Magnetic Resonance: new and old parameters in the natural history of repaired Tetralogy of Fallot.

BACKGROUND: Patients with repaired Tetralogy of Fallot (rTOF) often develop pulmonary regurgitation (PR) and right ventricle (RV) dysfunction, experiencing increased mortality and morbidity rates in adulthood. Pulmonary valve replacement (PVR) timing to address PR is controversial. Cardiac Magnetic Resonance (CMR) is the gold standard for morpho-functional evaluation of complex cardiopathies. This study aims to identify CMR parameters predictive of adverse outcomes to help defining the best therapeutic management of rTOF patients. METHODS: 130 rTOF patients who underwent CMR (2006-2019) were enrolled in this retrospective single-center study. CMR, clinical, ECG and exercise data were analyzed. Univariate and multivariate analyses identified clinical and CMR parameters predictive of adverse outcomes both individually (e.g., death, arrhythmias, heart failure (HF), pharmacological therapy, QRS ≥ 160ms) and as composite outcome. RESULTS: Univariate analysis confirmed RV volumes and RV ejection fraction corrected for PR as adverse outcome predictors and identified interesting correlations: pulmonary artery bifurcation geometry and abnormal interventricular septum (IVS) motion with arrhythmias (p < .001; p = .037), HF (p = .049; p = .005), composite outcome (p = .039; p = .009); right atrium (RA) dimensions with the composite outcome and the outcomes individually (p < .001). The best predictive models by multivariate analysis included sex (male), RV and RA dilation for QRS ≥ 160ms, time form repair to CMR, age at TOF repair and IVS fibrosis for pharmacological therapy. CONCLUSIONS: Besides RV volumes, new adverse prognostic factors could guide rTOF therapeutic management: pulmonary arteries morphology, abnormal IVS motion, RV dysfunction, RA dilation. Perspective multicentric evaluation is needed to specify their effective role.

Five-year follow-up after percutaneous pulmonary valve implantation using the Venus P-valve system for patients with pulmonary regurgitation and an enlarged native right ventricular outflow tract.

BACKGROUND: Percutaneous pulmonary valve implantation (PPVI) with the self-expandable Venus P-valve system is a promising treatment for patients with pulmonary regurgitation (PR) and a native right ventricular outflow tract (RVOT). However, limited data is available regarding its midterm outcomes. This study assessed the midterm clinical and echocardiographic outcomes following Venus P-valve implantation. METHODS: From 2013 to 2018, 55 patients with moderate or severe PR after surgical RVOT repair with a transannular or RVOT patch were consecutively enrolled from six hospitals in China. Five-year clinical and echocardiographic outcomes were collected and evaluated. The primary endpoint was a freedom from all-cause mortality and reintervention. RESULTS: At 5 years, the primary endpoint was met for 96% of patients, corresponding to a freedom from all-cause mortality of 96% (95% confidence interval [CI]: 86%-99%) and freedom from reintervention of 98% (95% CI: 87%-100%). Endocarditis was reported in five patients (four patients within 1 year and one patient at 5 years) following PPVI. Transpulmonary gradient and stent orifice diameter remained stable compared to at discharge (p＞0.05). No paravalvular leak was reported while only 1 patient gradually increased to moderate PR during follow-up. Significant improvement of RV diameter and LVEF (p＜0.001) sustained over the 5-year follow-up, in consistent with remarked improved New York Heart Association(NYHA) functional class (p＜0.001). CONCLUSION: The 5-year results of the China VenusP Study demonstrated the midterm benefits of Venus P-valve implantation in the management of patients with severe PR with an enlarged native RVOT by providing sustained symptomatic and hemodynamic improvement.

Pulmonary valve replacement in tetralogy of Fallot - who and how?

BACKGROUND AND AIM: Pulmonary regurgitation is the most common complication in repaired tetralogy of Fallot patients. Severe chronic pulmonary regurgitation can be tolerated for decades, but if not treated, it can progress to symptomatic, irreversible right ventricular dilatation and dysfunction. We investigated clinical associations with pulmonary valve replacement among patients with significative pulmonary regurgitation and how interventional developments can change their management. METHODS: All adult patients with repaired tetralogy of Fallot who were followed at an adult CHD Clinic at a single centre from 1980 to 2022 were included on their first outpatient visit. Follow-up was estimated from the time of correction surgery until one of the following events occurred first: pulmonary valve replacement, death, loss to follow-up or conclusion of the study. RESULTS: We included 221 patients (116 males) with a median age of 19 (18-25). At a median age of 33 (10) years old, 114 (51%) patients presented significant pulmonary regurgitation. Among patients with significant pulmonary regurgitation, pulmonary valve replacement was associated with male gender, older age at surgical repair, and longer QRS duration in adulthood. Pulmonary valve replacement was performed in 50 patients, including four transcatheter pulmonary valve implantations, at a median age of 34 (14) years. CONCLUSION: Pulmonary regurgitation affects a large percentage of tetralogy of Fallot adult patients, requiring a long-term clinical and imaging follow-up. Sex, age at surgical repair and longer QRS are associated with the need of PVR among patients with significative pulmonary regurgitation. Clinical practice and current literature support TPVI as the future gold standard intervention.

Pulmonary Valve Replacement in Tetralogy of Fallot: Procedural Volume and Durability of Bioprosthetic Pulmonary Valves.

BACKGROUND: Robust data on changes in pulmonary valve replacement (PVR) procedural volume and predictors of bioprosthetic pulmonary valve (BPV) durability in patients with tetralogy of Fallot (TOF) are scarce. OBJECTIVES: This study sought to assess temporal trends in PVR procedural volume and BPV durability in a nationwide, retrospective TOF cohort. METHODS: Data were obtained from patient records. Robust linear regression was used to assess temporal trends in PVR procedural volume. Piecewise exponential additive mixed models were used to estimate BPV durability, defined as the time from implantation to redo PVR with death as a competing risk, and to assess risk factors for reduced durability. RESULTS: In total, 546 PVR were performed in 384 patients from 1976 to 2021. The annual number of PVR increased from 0.4 to 6.0 per million population (P < 0.001). In the last decade, the transcatheter PVR volume increased by 20% annually (P < 0.001), whereas the surgical PVR volume did not change significantly. The median BPV durability was 17 years (Q1: 10-Q3: 10 years-not applicable). There was no significant difference in the durability of different BPV after adjustment for confounders. Age at PVR (HR: 0.78 per 10 years from <1 year; 95% CI: 0.63-0.96; P = 0.02) and true inner valve diameter (9-17 mm vs 18-22 mm HR: 0.40; 95% CI: 0.22-0.73; P = 0.003 and 18-22 mm vs 23-30 mm HR: 0.59; 95% CI: 0.25-1.39; P = 0.23) were associated with reduced BPV durability in multivariate models. CONCLUSIONS: The PVR procedural volume has increased over time, with a greater increment in transcatheter than surgical PVR during the last decade. Younger patient age at PVR and a smaller true inner valve diameter predicted reduced BPV durability.

Right ventricular outflow tract obstruction associated with neointimal tissue accumulation and distortion of the Harmony TPV25 stent frame: Potential mechanisms and treatment.

BACKGROUND: The Harmony TPV25 transcatheter pulmonary valve (Medtronic Inc.) is constructed with a self-expanding stent frame comprising six zigged nitinol wires sewn together and covered with knitted polyester fabric, with flared inflow and outflow ends and a porcine pericardial valve sutured to the central portion of the device. It was approved for treatment of pulmonary regurgitation after prior right ventricular outflow tract repair in 2021. Early outcomes of this procedure have been excellent, but little is known about valve durability or ultimate mechanisms of dysfunction. METHODS: We collected data on patients who underwent reintervention for TPV25 dysfunction and described findings related to distortion of the stent frame and tissue accumulation. RESULTS: We describe six patients who underwent valve-in-valve implant for TPV25 obstruction (peak catheterization gradient peak 28-73 mmHg) 10-28 months after implant. In all cases, there was tissue accumulation within the inflow and valve-housing segments of the device and deformation of the self-expanding valve frame characterized by variable circumferential narrowing at the junction between the valve housing and the inflow and outflow portions of the device, with additional geometric changes in all segments. All six patients underwent valve-in-valve implant that results in a final peak gradient ≤10 mmHg and no regurgitation. DISCUSSION: The occurrence of short-term Harmony TPV25 dysfunction in multiple patients with a similar appearance of frame distortion and tissue accumulation within the inflow and valve housing portions of the device suggests that this may be an important failure mechanism for this valve. Potential causes of the observed findings are discussed. It is possible to treat this mechanism of TPV25 dysfunction with valve-in-valve implant using balloon expandable transcatheter valves.

Right ventricular dilatation score: a new assessment to right ventricular dilatation in adult patients with repaired tetralogy of Fallot.

BACKGROUND: Patients with repaired tetralogy of Fallot (rTOF) experience long-term chronic pulmonary valve regurgitation resulting in right ventricular (RV) dilatation. According to current guidelines, the evaluation of patients with rTOF for RV dilatation should be based on cardiac magnetic resonance (CMR). However, for many asymptomatic patients, routine CMR is not practical. Our study aims to identify screening methods for CMR based on echocardiographic data, with the goal of establishing a more practical and cheap method of screening for severity of RV dilatation in patients with asymptomatic rTOF. METHODS: Thirty two rTOF patients (mean age, 21(10.5) y, 21 males) with moderate to severe pulmonary regurgitation (PR) were prospectively recruited. Each patient received CMR and echocardiogram examination within 1 month prior to operation and collected clinical data, and then received echocardiogram examination at discharge and 3-6 months post-surgery. RESULTS: RV moderate-severe dilatation was defined as right ventricular end-diastolic volume index (RVEDVI) ≥ 160 ml/m2 or right ventricular end-systolic volume index (RVESVI) ≥ 80 ml/m2 in 15 of 32 patients (RVEDVI, 202.15[171.51, 252.56] ml/m2, RVESVI, 111.99 [96.28, 171.74] ml/m2). The other 17 (RVESDI, 130.19 [117.91, 139.35] ml/m2, RVESVI = 67.91 [63.35, 73.11] ml/m2) were defined as right ventricle mild dilatation, i.e., RVEDVI < 160 ml/m2 and RVESVI < 80 ml/m2, and the two parameters were higher than normal values. Compared with the RV mild dilatation group, patients of RV moderate-severe dilatation have worse cardiac function before surgery (right ventricular ejection fraction, 38.92(9.19) % versus 48.31(5.53) %, p < 0.001; Left ventricular ejection fraction, 59.80(10.26) versus 66.41(4.15), p = 0.021). Patients with RV moderate-severe dilatation faced longer operation time and more blood transfusion during operation (operation time, 271.53(08.33) min versus 170.53(72.36) min, p < 0.01; Intraoperative blood transfusion, 200(175) ml versus 100(50) ml, p = 0.001). Postoperative RV moderate-severe dilatation patients have poor short-term prognosis, which was reflected in a longer postoperative hospital stay (6.59 [2.12] days versus 9.80 [5.10] days, p = 0.024) and a higher incidence of hypohepatia (0[0] % versus 4[26.7] %, p = 0.023). Patients with RV dilatation score > 2.35 were diagnosed with RV moderate-severe dilatation (AUC = 0,882; Sensitivity = 94.1%; Specificity = 77.3%). CONCLUSIONS: RV moderate-severe dilatation is associated with worse preoperative cardiac function and short-term prognosis after PVR in rTOF patients with moderate to severe PR. The RV dilatation score is an effective screening method. When RV dilatation score > 2.35, the patient is indicated for further CMR examination and treatment.

Physician-Modified Endograft-Facilitated Transcatheter Pulmonary Valve Replacement in Large Right Ventricular Outflow Tract.

BACKGROUND: Transcatheter pulmonary valve replacement (TPVR) in patients with a congenital or acquired abnormality resulting in enlarged right ventricular outflow tract (RVOT) is challenging and may preclude treatment with dedicated devices. We describe a technique using a physician-modified endograft to facilitate TPVR. METHODS: Six patients underwent physician-modified endograft-facilitated TPVR for severe symptomatic pulmonary insufficiency with enlarged RVOT. The fenestration was created in a commercially available endograft before implantation, which was then deployed from the dominant branch pulmonary artery into the RVOT, with the fenestration aligned with the ostium of the nondominant pulmonary artery. A covered stent was placed through the fenestration into the nondominant branch pulmonary artery, and a transcatheter heart valve was deployed within the endograft at the level of the original pulmonary valve. RESULTS: Four patients had tetralogy of Fallot, 1 had pulmonary atresia, and 1 had rheumatic valve disease. The RVOT/main pulmonary artery was severely enlarged (diameter, 44.2 [43.5-50.6] mm). All patients had reduced right ventricular (RV) function and dilated RVs (RV end-diastolic volume, 314 [235-316] mL). Successful endograft, covered stent, and transcatheter heart valve deployment were achieved in all cases without stent/valve embolization, vascular complications, or bleeding complications. At 30 days, 1 patient had mild pulmonary insufficiency, while others had none. The RV size measured by echocardiography was significantly reduced after TPVR (RV area, 34.4 [baseline] versus 29.0 [pre-discharge] versus 25.3 [30 days] cm2; P=0.03). During median follow-up of 221.5 (range, 29-652) days, there were no deaths or need for pulmonary valve reintervention. One patient developed severe tricuspid regurgitation due to entrapment of the anterior tricuspid leaflet by the endograft. The patient underwent successful tricuspid replacement and resection of the offending endograft with preservation of the pulmonary valve prosthesis. CONCLUSIONS: Simple fenestration of an off-the-shelf endograft and associated covered stent placement through the fenestration allows TPVR for patients with dysfunctional native or patch-repaired pulmonary valves and RVOT enlargement.

QRS Duration After Pulmonary Valve Replacement in Adults with Repaired Tetralogy of Fallot: Association with Ventricular Arrhythmia and Correlation with Right Ventricular Size.

The aim of this study is to analyze the relationship between QRS duration after pulmonary valve replacement (PVR) and ventricular arrhythmias (VA) in patients with repaired tetralogy of Fallot (ToF). ToF patients may face complications such as heart failure and VA after primary repair, often mitigated by PVR. Prior studies have shown a decrease in QRS duration and right ventricular (RV) size following PVR. It remains unclear whether a lack of QRS duration reduction identifies patients at risk of VA. We retrospectively identified adult patients with repaired ToF who underwent surgical or transcatheter PVR. EKG data (pre-PVR, 30 days to 1-year post-PVR, and closest to CMR) was collected. The primary endpoint was sustained ventricular tachycardia (VT), ICD shock for sustained VT, or inducible VT on EP study. 85 patients were included (median follow-up 3.6 years; median age 34 years; 51% females). The primary outcome was noted in 8 patients. Mean QRS duration decreased by 5 ms following PVR (p = 0.0001). Increased age at PVR, QRS ≥ 180 ms post-PVR, no reduction in QRS after PVR, and a history of VT were associated with higher risk of the primary endpoint. The change in QRS was linearly correlated with the change in RVEDVi (R = 0.66). Adults with repaired ToF experience a reduction in QRS duration post-PVR that correlates with the change of the RV size. Patients with QRS ≥ 180 ms post-PVR, no reduction in QRS, increased age at repair, and a history of VT are at risk for recurrent VT and warrant closer monitoring/ICD consideration.

Rightward imbalanced pulmonary perfusion predicts better exercise stroke volume in children after Fallot repair.

BACKGROUND: Residual lesions following Fallot repair are primarily pulmonary regurgitation and right ventricular outflow tract obstruction. These lesions may impact exercise tolerance, particularly because of a poor increase in left ventricular stroke volume. Pulmonary perfusion imbalance is also common, but its effect on cardiac adaptation to exercise is not known. AIM: To assess the association between pulmonary perfusion asymmetry and peak indexed exercise stroke volume (pSVi) in young patients. METHODS: We retrospectively studied 82 consecutive patients with Fallot repair (mean age 15.2±3.8 years) who underwent echocardiography, four-dimensional flow magnetic resonance imaging and cardiopulmonary testing with pSVi measurement by thoracic bioimpedance. Normal pulmonary flow distribution was defined as right pulmonary artery perfusion between 43 and 61%. RESULTS: Normal, rightward and leftward flow distributions were found in 52 (63%), 26 (32%) and four (5%) patients, respectively. Independent predictors of pSVi were right pulmonary artery perfusion (ß=0.368, 95% confidence interval [CI] 0.188 to 0.548; P=0.0003), right ventricular ejection fraction (ß=0.205, 95% CI 0.026 to 0.383; P=0.049), pulmonary regurgitation fraction (ß=-0.283, 95% CI -0.495 to -0.072; P=0.006) and Fallot variant with pulmonary atresia (ß=-0.213, 95% CI -0.416 to -0.009; P=0.041). The pSVi prediction was similar when the categorical variable right pulmonary artery perfusion>61% was used (ß=0.210, 95% CI 0.006 to 0.415; P=0.044). CONCLUSION: In addition to right ventricular ejection fraction, pulmonary regurgitation fraction and Fallot variant with pulmonary atresia, right pulmonary artery perfusion is a predictor of pSVi, in that rightward imbalanced pulmonary perfusion favours greater pSVi.

1-Year Outcomes in a Pooled Cohort of Harmony Transcatheter Pulmonary Valve Clinical Trial Participants.

BACKGROUND: The Harmony transcatheter pulmonary valve (TPV) is the first U.S. Food and Drug Administration-approved device for severe pulmonary regurgitation (PR) in the native or surgically repaired right ventricular outflow tract (RVOT). OBJECTIVES: One-year safety and effectiveness of the Harmony TPV were evaluated in patients from the Harmony Native Outflow Tract Early Feasibility Study, Harmony TPV Pivotal Study, and Continued Access Study, representing the largest cohort to date of Harmony TPV recipients. METHODS: Eligible patients had severe PR by echocardiography or PR fraction ≥ 30% by cardiac magnetic resonance imaging and clinical indications for pulmonary valve replacement. The primary analysis included 87 patients who received a commercially available TPV22 (n = 42) or TPV25 (n = 45) device; 19 patients who received an early device iteration prior to its discontinuation were evaluated separately. RESULTS: In the primary analysis, median patient age at treatment was 26 years (IQR: 18-37 years) in the TPV22 group and 29 years (IQR: 19-42 years) in the TPV25 group. At 1 year, there were no deaths; 98% of TPV22 and 91% of TPV25 patients were free from the composite of PR, stenosis, and reintervention (moderate or worse PR, mean RVOT gradient >40 mmHg, device-related RVOT reoperation, and catheter reintervention). Nonsustained ventricular tachycardia occurred in 16% of patients. Most patients had none/trace or mild PR (98% of TPV22 patients, 97% of TPV25 patients). Outcomes with the discontinued device are reported separately. CONCLUSIONS: The Harmony TPV device demonstrated favorable clinical and hemodynamic outcomes across studies and valve types through 1 year. Further follow-up will continue to assess long-term valve performance and durability.

Systematic Electrophysiological Study Prior to Pulmonary Valve Replacement in Tetralogy of Fallot: A Prospective Multicenter Study.

BACKGROUND: Ventricular arrhythmias and sudden death are recognized complications in tetralogy of Fallot. Electrophysiological studies (EPS) before pulmonary valve replacement (PVR), the most common reintervention in tetralogy of Fallot, could potentially inform therapy to improve arrhythmic outcomes. METHODS: A prospective multicenter study was conducted to systematically assess EPS with programmed ventricular stimulation in patients with tetralogy of Fallot referred for PVR from January 2020 to December 2021. A standardized stimulation protocol was used across all centers. RESULTS: A total of 120 patients were enrolled, mean age 39.2±14.5 years, 53.3% males. Sustained ventricular tachycardia was induced in 27 (22.5%) patients. When identifiable, the critical isthmus most commonly implicated (ie, in 90.0%) was between the ventricular septal defect patch and pulmonary annulus. Factors independently associated with inducible ventricular tachycardia were history of atrial arrhythmia (odds ratio, 8.56 [95% CI, 2.43-34.73]) and pulmonary annulus diameter >26 mm (odds ratio, 5.05 [95% CI, 1.47-21.69]). The EPS led to a substantial change in management in 23 (19.2%) cases: 18 (15.0%) had catheter ablation, 3 (2.5%) surgical cryoablation during PVR, and 9 (7.5%) defibrillator implantation. Repeat EPS 5.1 (4.8-6.2) months after PVR was negative in 8 of 9 (88.9%) patients. No patient experienced a sustained ventricular arrhythmia during 13 (6.1-20.1) months of follow-up. CONCLUSIONS: Systematically performing programmed ventricular stimulation in patients with tetralogy of Fallot referred for PVR yields a high rate of inducible ventricular tachycardia and carries the potential to alter management. It remains to be determined whether a standardized treatment approach based on the results of EPS will translate into improved outcomes. REGISTRATION: URL: https://clinicaltrials.gov/ct2/show/NCT04205461; Unique identifier: NCT04205461.